Pregnant women can gain a stronger immune system with H1N1 vaccine

Healthy pregnant women who received the current swine flu shot are developing a robust immune response with just one shot containing the 2009 H1N1 influenza vaccine, say federal officials monitoring the 2009 flu vaccination campaign.

“For pregnant women, who are among the most vulnerable to serious health problems from 2009 H1N1 infection, these initial results are very reassuring,” says Anthony S. Fauci, MD, director of the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health.”The immune responses seen in these healthy pregnant women are comparable to those seen in healthy adults at the same time point after a single vaccination, and the vaccine has been well tolerated,”he said of the initial results from an ongoing clinical trial sponsored by the NIAID.

As of the end of October, at least 100 pregnant women have been hospitalized in intensive care units in the United States and at the last official count, 28 pregnant women have died, according to the Centers for Disease Control and Prevention, since the outbreak began last spring,

A preliminary analysis of blood samples taken 21 days post-vaccination from a subgroup of 50 pregnant women participating in the trial showed that 92% to 96% of all women developed a likely protective response to the virus. All participants in the study were between 18 to 39 years old and began the study in their second or third trimester (14 to 34 weeks) of pregnancy.

Safety is being monitored closely in the trial, by the study investigators and by an independent panel of experts known as a safety monitoring committee. To date, the vaccine appears to be well-tolerated, and no safety concerns related to the vaccine have arisen, federal experts say.